- AS112
The AS112 project is a group of volunteer-administered name server operators, who run an
anycast instance ofname server s that answer for the RFC 1918reverse DNS networks, and the reverse address space of link-local RFC 3330 and RFC 3927 networks.# 10.0.0.0/8
# 169.254.0.0/16
# 172.16.0.0/12
# 192.168.0.0/16All of the AS112 nodes were originally run by a few of the
Root nameserver operators, but later the group of volunteers has grown to include many other organizations.Background
Before 2001, the in-addr.arpa zones for the RFC 1918 networks were delegated to a single instance of name servers, "blackhole-1.iana.org" and "blackhole-2.iana.org". The IANA-run servers were under increasing load from improperly-configured NAT networks, leaking out
reverse DNS queries, which eventually caused unnecessary load on the root servers. The decision was made by a small subset of root server operators to run the reverse delegations using a model as described in RFC 3258; each announcing the network using theautonomous system number of 112.pecific Configuration
The name servers participating in the AS112 project are each configured to answer authoritatively for the following zones:
* For the 10.0.0.0/8 network:
** 10.in-addr.arpa
* For the 169.254.0.0/16 network (RFC 3927)
** 254.169.in-addr.arpa
* For the 172.16.0.0/12 network:
** 16.172.in-addr.arpa
** 17.172.in-addr.arpa
** 18.172.in-addr.arpa
** 19.172.in-addr.arpa
** 20.172.in-addr.arpa
** 21.172.in-addr.arpa
** 22.172.in-addr.arpa
** 23.172.in-addr.arpa
** 24.172.in-addr.arpa
** 25.172.in-addr.arpa
** 26.172.in-addr.arpa
** 27.172.in-addr.arpa
** 28.172.in-addr.arpa
** 29.172.in-addr.arpa
** 30.172.in-addr.arpa
** 31.172.in-addr.arpa
* For the 192.168.0.0/16 network:
** 168.192.in-addr.arpa
* For unique identification purposes:
** hostname.as112.netExternal Sources
* [http://www.as112.net/ AS112 web page]
* [http://www.rssac.org/meetings/99-03/2002AtlantaUS.html RSSAC Meeting Atlanta 2002] Notes describing RFC 1918 network queries impact on the Root servers.
* [http://lists.oarci.net/pipermail/as112-ops/2006-December/000001.html Mailing list] for AS112 operators.
* [http://www.chagreslabs.net/jmbrown/research/as112/ Building] an AS112 node.
* [http://emj.se/2008/01/23/as112-node-running-freebsd-and-openbgpd/ Building] an AS112 node using FreeBSD and OpenBGPD
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